yep they are fine. Mia sleeps with a dummy. Usually she spits it out once shes in a deep sleep, sometimes she doesnt. It might be the shape of the Nuk ones thats leaving red marks. There are so many dummies out there so mayb try a different one? I tried heaps before I found one she was happy with and it was the Tommee Tippee ones. There are so many different shapes and sizes.. i was quite amazed.